Ms. Franklin was a veteran stage and television performer before ‘‘One Day At a Time’’ made her a star.

Developed by Norman Lear and cocreated by Whitney Blake — a former sitcom star and single mother raising ­future actress Meredith Baxter — the series was groundbreaking for its focus on a divorced mother seeking independence from a suffocating marriage.

It premiered on CBS in ­December 1975, just five years after the network had balked at having Mary Tyler Moore play a divorced woman on her own comedy series, insisting that newly single Mary Richards be portrayed as having ended her engagement instead.

On her own in Indianapolis, Ann Romano was raising two teenage girls, played by Mackenzie Phillips, already famous for the film ‘‘American Graffiti,’’ and a previously unknown Valerie Bertinelli. ‘‘One Day At a Time’’ ran on CBS until 1984, by which time both daughters had grown and married, while Romano had remarried and become a grandmother. During the first seven of its nine seasons, the show was a Top 20 hit.

Like other Lear productions such as ‘‘All in the Family’’ and ‘‘Good Times,’’ “One Day at a Time’’ dealt with contemporary issues once absent from television comedies such as premarital sex, birth control, suicide, and sexual harassment, issues that had been overlooked by television comedies whose households were usually headed by a husband and wife or, rarely, a widowed parent.

Meanwhile, the series weathered crises as Phillips was twice written out of it to deal with her drug abuse and other personal problems.

Writing in her 2009 memoir ‘‘High On Arrival,’’ Phillips remembered Ms. Franklin as hard-working and professional.

‘‘Bonnie felt a responsibility to the character and always gave a million notes on the scripts,’’ Phillips wrote. ‘‘Above all, she didn’t want it to be sitcom fluff — she wanted it to deal honestly with the struggles and truths of raising two teenagers as a single mother.’’

In her 2008 memoir ‘‘Losing It,’’ Bertinelli noted that Ms. Franklin, just 31 when the show began, was not old enough to be her real mother.

Even so, wrote Bertinelli, ‘‘within a few days I recognized her immense talent and felt privileged to work with her. . . . She was like a hip, younger complement to my real mom.’’

The truth of ‘‘One Day at a Time’’ was brought home to Ms. Franklin when in 2005 she got together with both television daughters for a ‘‘One Day at a Time’’ reunion special. She told both actresses, ‘‘You are living, in a sense, Ann Romano’s life — you are single parents raising teenage kids. That is shocking and terrifying to me.’’

Ms. Franklin was married for 29 years. Her husband, television producer Marvin Minoff, died in 2009.